Revising simple lenses - magnified, and diminished images

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Understanding whether an image is magnified or diminished involves analyzing the object distance (O.D.) in relation to the focal length (F) of the lens. The geometry of the object at various distances indicates whether the images are real or virtual, inverted or upright, and magnified or diminished. The image distance affects perception; a diminished image closer to the eye may appear larger, while a magnified virtual image further away could seem smaller. The complexity increases when considering the eye as a lens itself, which means calculations must account for both lenses. Ultimately, determining perceived size requires evaluating the combined effects of both lenses on the image.
RK1992
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Basically, I'm trying to revise lenses and the one thing I never really understood was how to tell whether an image is magnified or diminished.

http://store.aqa.org.uk/qual/gce/pdf/AQA-2450-W-TRB-OGA.PDF pages 6 and 7 has the diagrams to show what I mean

I can do the geometry of an object at points where:
O.D. > 2F;
O.D. = 2F;
2F > O.D. > F and
F > O.D. > 0
to show that the images formed are real/virtual, inverted/upright and magnified/diminshed but I'm not really sure what the image distance means.. if the image is diminished but the image is nearer to you, how do you know whether it would appear bigger or smaller? Likewise with a magnified virtual image which is further away than the object. :redface:

Thanks
 
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I am not positive but it seems like your intuition about a magnified image being far from your eye mean that is would not be as magnified. The one thing I will say is that things a more complicated when you include your eye because your eye contains a lens. So, now you have two lenses in the problem. The magnification of the images in question are in relation to that single lens. If you want to figure out what your eye will see then you need to work through with a second lens.
 
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